Hemodynamic performance of NMES in the early post operative period following orthopaedic surgery

Patients post total hip arthroplasty (THA) remain at high risk of developing Deep Vein Thrombosis (DVT) during the recovery period following surgery. The use of calf muscle neuromuscular electrical stimulation (NMES) during the hospitalized recovery period on this patient group may be effective at preventing DVT. However, the haemodynamic effectiveness and comfort characteristics of NMES in post-THA patients immediately following surgery has yet to be demonstrated. The popliteal veins of 5 patients, who had undergone unilateral total hip replacement surgery on the day previous to the study, were measured using Doppler ultrasound during a 4 hour calf-muscle NMES session. The effect of calf muscle NMES on peak venous velocity and volume flow were compared to resting values. Comfort was assessed using a 100 mm non-hatched visual analogue scale taken before application of NMES, once NMES was initiated and before NMES was withdrawn. Results of the study showed that NMES produces a beneficial hemodynamic response in patients in the early postoperative period following orthopaedic surgery. This patient group found extended periods of calf-muscle NMES tolerable.